Description: (Applicant's Description) The UPCI Cytogenetics Facility provides cancer researchers with state-of-the-art classical and molecular cytogenetic technologies to investigate constitutional or acquired genetic alterations in human or animal cells and map critical genes and viral or transgene integration sites (http://www.upci.upmc.edu/cytogen/). The UPCI Cytogenetics Facility is an increasingly utilized resource that has provided results and consultation to funded cancer researchers at the UPCI and other universities. For example, the Facility has been involved in several projects concerning liver carcinogenesis and several studies involving oral cancer. One project involved the use of the Facility in mapping the homeobox gene, Nkx2.8, for Dr. Joseph Locker of the Molecular and Cellular Oncology Program. Nkx2.8 is a novel transcription factor cloned from HepG2 cells and human fetal liver. Using sequential high-resolution G-banding and fluorescence in situ hybridization (FISH), we mapped the gene to 14q13, the locus of several other developmental genes associated with foregut structures, notably Nkx2.1/TTF1 and HNF3-alpha, which may be regulatory target of Nkx2.8. A recent study for Dr. Susanne Gollin of the Head and Neck Cancer Program, involved evaluation of CDKN2A (p16) tumor suppressor gene copy number loss in oral cancer, which revealed a statistically significant association between homozygous CDKN2A deletion and recurrence of oral cancer. These and other studies will be discussed in greater detail in the body of the proposal. Genetic analysis is playing an increasingly prominent role in cancer research and the UPCI Cytogenetics Facility provides services essential to support the needs of the UPCI scientific community.